From: Cody P Schafer <cody@linux.vnet.ibm.com>
To: Simon Jeons <simon.jeons@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mgorman@suse.de>, Linux MM <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/3] mm: fixup changers of per cpu pageset's ->high and ->batch
Date: Mon, 08 Apr 2013 12:37:20 -0700 [thread overview]
Message-ID: <51631C70.8010404@linux.vnet.ibm.com> (raw)
In-Reply-To: <5160CC94.6040909@gmail.com>
On 04/06/2013 06:32 PM, Simon Jeons wrote:
> Hi Cody,
> On 04/06/2013 04:33 AM, Cody P Schafer wrote:
>> In one case while modifying the ->high and ->batch fields of per cpu
>> pagesets
>> we're unneededly using stop_machine() (patches 1 & 2), and in another
>> we don't have any
>> syncronization at all (patch 3).
>
> Do you mean stop_machine() is used for syncronization between each
> online cpu?
>
I mean that it looks like synchronization between cpus is unneeded
because of how per cpu pagesets are used, so stop_machine() (which does
provide syncro between all cpus) is unnecessarily "strong".
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
WARNING: multiple messages have this Message-ID (diff)
From: Cody P Schafer <cody@linux.vnet.ibm.com>
To: Simon Jeons <simon.jeons@gmail.com>
Cc: Andrew Morton <akpm@linux-foundation.org>,
Mel Gorman <mgorman@suse.de>, Linux MM <linux-mm@kvack.org>,
LKML <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH 0/3] mm: fixup changers of per cpu pageset's ->high and ->batch
Date: Mon, 08 Apr 2013 12:37:20 -0700 [thread overview]
Message-ID: <51631C70.8010404@linux.vnet.ibm.com> (raw)
In-Reply-To: <5160CC94.6040909@gmail.com>
On 04/06/2013 06:32 PM, Simon Jeons wrote:
> Hi Cody,
> On 04/06/2013 04:33 AM, Cody P Schafer wrote:
>> In one case while modifying the ->high and ->batch fields of per cpu
>> pagesets
>> we're unneededly using stop_machine() (patches 1 & 2), and in another
>> we don't have any
>> syncronization at all (patch 3).
>
> Do you mean stop_machine() is used for syncronization between each
> online cpu?
>
I mean that it looks like synchronization between cpus is unneeded
because of how per cpu pagesets are used, so stop_machine() (which does
provide syncro between all cpus) is unnecessarily "strong".
next prev parent reply other threads:[~2013-04-08 19:37 UTC|newest]
Thread overview: 60+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-04-05 20:33 [PATCH 0/3] mm: fixup changers of per cpu pageset's ->high and ->batch Cody P Schafer
2013-04-05 20:33 ` Cody P Schafer
2013-04-05 20:33 ` [PATCH 1/3] mm/page_alloc: factor out setting of pcp->high and pcp->batch Cody P Schafer
2013-04-05 20:33 ` Cody P Schafer
2013-04-07 1:37 ` Simon Jeons
2013-04-07 1:37 ` Simon Jeons
2013-04-08 17:39 ` Cody P Schafer
2013-04-08 17:39 ` Cody P Schafer
2013-04-09 5:42 ` Simon Jeons
2013-04-09 5:42 ` Simon Jeons
2013-04-05 20:33 ` [PATCH 2/3] mm/page_alloc: convert zone_pcp_update() to use on_each_cpu() instead of stop_machine() Cody P Schafer
2013-04-05 20:33 ` Cody P Schafer
2013-04-07 15:39 ` KOSAKI Motohiro
2013-04-07 15:39 ` KOSAKI Motohiro
2013-04-08 17:32 ` Cody P Schafer
2013-04-08 17:32 ` Cody P Schafer
2013-04-08 19:26 ` KOSAKI Motohiro
2013-04-08 19:26 ` KOSAKI Motohiro
2013-04-08 19:49 ` Cody P Schafer
2013-04-08 19:49 ` Cody P Schafer
2013-04-08 22:18 ` KOSAKI Motohiro
2013-04-08 22:18 ` KOSAKI Motohiro
2013-04-09 1:52 ` Cody P Schafer
2013-04-09 1:52 ` Cody P Schafer
2013-04-05 20:33 ` [PATCH 3/3] mm: when handling percpu_pagelist_fraction, use on_each_cpu() to set percpu pageset fields Cody P Schafer
2013-04-05 20:33 ` Cody P Schafer
2013-04-07 1:56 ` Simon Jeons
2013-04-07 1:56 ` Simon Jeons
2013-04-08 17:34 ` Cody P Schafer
2013-04-08 17:34 ` Cody P Schafer
2013-04-07 15:41 ` KOSAKI Motohiro
2013-04-07 15:41 ` KOSAKI Motohiro
2013-04-08 12:20 ` Gilad Ben-Yossef
2013-04-08 12:20 ` Gilad Ben-Yossef
2013-04-08 17:28 ` Cody P Schafer
2013-04-08 17:28 ` Cody P Schafer
2013-04-08 19:50 ` Cody P Schafer
2013-04-08 19:50 ` Cody P Schafer
2013-04-08 22:23 ` KOSAKI Motohiro
2013-04-08 22:23 ` KOSAKI Motohiro
2013-04-09 6:03 ` Gilad Ben-Yossef
2013-04-09 6:03 ` Gilad Ben-Yossef
2013-04-09 6:06 ` Gilad Ben-Yossef
2013-04-09 6:06 ` Gilad Ben-Yossef
2013-04-09 19:27 ` Cody P Schafer
2013-04-09 19:27 ` Cody P Schafer
2013-04-08 19:16 ` KOSAKI Motohiro
2013-04-08 19:16 ` KOSAKI Motohiro
2013-04-07 1:32 ` [PATCH 0/3] mm: fixup changers of per cpu pageset's ->high and ->batch Simon Jeons
2013-04-07 1:32 ` Simon Jeons
2013-04-08 19:37 ` Cody P Schafer [this message]
2013-04-08 19:37 ` Cody P Schafer
2013-04-07 15:23 ` KOSAKI Motohiro
2013-04-07 15:23 ` KOSAKI Motohiro
2013-04-08 17:16 ` Cody P Schafer
2013-04-08 17:16 ` Cody P Schafer
2013-04-08 19:08 ` KOSAKI Motohiro
2013-04-08 19:08 ` KOSAKI Motohiro
2013-04-08 21:17 ` Cody P Schafer
2013-04-08 21:17 ` Cody P Schafer
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=51631C70.8010404@linux.vnet.ibm.com \
--to=cody@linux.vnet.ibm.com \
--cc=akpm@linux-foundation.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-mm@kvack.org \
--cc=mgorman@suse.de \
--cc=simon.jeons@gmail.com \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.